In pipeline operations and other industrial applications, flowmeters are used to measure the volumetric flow rate of a gaseous or liquid flow stream moving through a piping section. Flowmeters can include an orifice fitting, which orients and supports an orifice plate in a plate carrier that extends across the piping section perpendicular to the direction of the flow stream. A dual chamber orifice fitting allows the plate carrier be removed from the fitting without interrupting the flow stream moving through the piping section.